NTSB finds design flaw caused Minneapolis bridge collapse

(AP) - Federal investigators have identified a design flaw as the cause of last year's Interstate 35-W bridge collapse in Minneapolis that killed 13 people.

That's according to a congressional official who was briefed by the National Transportation Safety Board.

The official says investigators found a design flaw in the bridge's gusset plates, which are the steel plates that tie steel beams together.

The findings are consistent with what the NTSB said about a week after the August 1st collapse, in which the bridge plunged into the Mississippi River.

The chairman of the NTSB, Mark Rosenker, is providing an official update on the probe later today.